Hi John. If you have the cash, go straight to MH. I have power compacts on my system and constantly have to make sure that the colors are ok on my clams and anemones as well as buy new lights every 6 months to keep the spectrum up. I also have too create a ledge high up in the tank for them to sit on - which costs more in liverock purchases. It would have been much easier if I would have just invested in a MH system. But as Matt said, the size of the tank will also be something to consider.